EddyLoop is a small app on purpose, and the docs match. Start with installing it, then read the rest as you need it.
Download the Windows installer, run it, and grant microphone access. The first launch fetches the speech model.
What happens on the first launch, where the model goes, and how to start your first session.
One plain text file per recording session, named for the time it started, in a folder you choose. Nothing is stored in a database and nothing is encrypted.